SAT0316 ANTI-PM/SCL ANTIBODIES IN SYSTEMIC SCLEROSIS: CLINICAL ASSOCIATIONS IN THE RESCLE COHORT

Background:Anti-PM/Scl antibodies are associated to systemic sclerosis (SSc) but are not specific to SSc. The true prevalence of anti-PM/Scl antibodies in SSc is unknown, ranging from 2.5% to 12.5%. An association between anti-PM/Scl antibodies with muscular involvement, pulmonary fibrosis, calcinosis, and a relatively benign prognosis have been described.Objectives:To compare the clinical manifestations and prognosis of SSc patients according the presence of anti-PM/Scl antibodies in the cohort of RESCLE (Spanish Scleroderma Registry).Methods:From the Spanish Scleroderma Study Group database, we selected patients in whom anti-PM/Scl antibodies had been tested. We compared demographic features, clinical manifestations, laboratory characteristics, and survival data between patients according the anti-PM/Scl antibodies status.Results:72 out of 947 (7%) patients tested positive for anti-PM/Scl antibodies. As presenting SSc manifestations, patients with anti-PM/Scl antibodies had higher prevalence of puffy fingers (11% versus 2%; p=0.002) and arthralgias (11% versus 4%; p=0.03), and lower prevalence of Raynaud’s phenomenon (65% versus 82%, p=0.002). Regarding cumulative manifestations, myositis (51% versus 15%; p<0.001), arthritis (43% versus 22%; p=0.001), and interstitial lung disease (ILD) (60% versus 45%, p=0.014) were more prevalent in patients with anti-PM/Scl antibodies. In fact, those patients with anti-Pm/Scl antibodies presented with FVC (77.4% ± 23.1% versus 85.8% ± 23,1%; p=0.006) and more severe ILD defined as FVC <70% (41% versus 24%; p=0.004). Death rate was similar in patients with and without PM/Scl antibodies (18% versus 17%; p=0.871).We did not find differences in terms of death rate nor in the causes of death (SSc and non-SSc related) according to the anti-PM/Scl antibodies profile.The 5- and 10-years survival rates of patients with anti-PM/Scl antibodies were 91% and 82% respectively, without differences with those without these antibodies (93% and 85%, respectively).Conclusion:In Spanish SSc patients, the presence of anti-PM/Scl antibodies confer a distinctive clinical profile. However, anti-PM/Scl antibodies do not play a role in the prognosis of these patients.References:[1]Stochmal A, Czuwara J, Trojanowska M, Rudnicka L. Antinuclear antibodies in systemic sclerosis: an update. Clin Rev Allergy Immunol 2020;58(1):40-51. doi: 10.1007/s12016-018-8718-8.Acknowledgments:We gratefully acknowledge all investigators who are part of the RESCLE Registry. We also thank the RESCLE Registry Coordinating Centre, S&H Medical Science Service, for their quality control data, logistic and administrative support and Prof. Salvador Ortiz, Universidad Autónoma de Madrid and Statistical Advisor S&H Medical Science Service for the statistical analysis of the data presented in this paper.Disclosure of InterestsNerea Iniesta-Arandia: None declared, Gerard Espinosa Speakers bureau: Glaxo-Smith-Kline, Janssen, Boehringer, Rovi, Alfredo Guillen del Castillo: None declared, Carles Tolosa Consultant of: Actelion pharmaceuticals, GSK, MSD., Gema Maria Lledó: None declared, Dolores Colunga Argüelles Consultant of: Actelion pharmaceuticals, GSK, MSD., Cristina González-Echávarri: None declared, Luis Sáez-Comet: None declared, Norberto Ortego: None declared, Jose Antonio Vargas-Hitos: None declared, Manuel Rubio-Rivas: None declared, Mayka Freire: None declared, Juan José Rios: None declared, Monica Rodriguez-Carballeira: None declared, Luis Trapiella Martínez: None declared, Vicent Fonollosa Pla Speakers bureau: Actelion, Carmen Pilar Simeón-Aznar Consultant of: Actelion pharmaceuticals, GSK, MSD., on behalf of RESCLE Investigators, Autoimmune Diseases Study Group (GEAS): None declared